Nope, but there's only one restore point - created automatically on Friday evening - so that doesn't help. (Ticked the "Show more" checkbox and nothing else appears. Damned thing.)
I have no other active Windows boxes, and I'm not faffing around finding and swapping the harddrive I took out of my netbook since I'm approximately 5000% certain the NAS is correctly configured and the issue is with this Windows instance.